Increasingly sophisticated methods to visualize tissue/cellular structure/neuronal circuits and to monitor real-time molecular interactions and biochemical reactions, have contributed to recent progress both in developmental neurobiology and in studying neurodevelopmental disorders. Current advancement has been augmented by access to specific antibodies for immunostaining, cloning of nucleic acids and in situ hybridization, new dyes and cell labeling techniques, in combination with a diverse array of powerful new microscopes. Imaging technologies such as laser scanning confocal microscopy, multiphoton excitation fluorescence, fluorescence recovery after photobleaching (FRAP), fluorescence resonance energy transfer (FRET), Spinning Disk Confocal microscopy and Array Tomography offer greatly increased resolution of cellular processes and require sophisticated analysis programs. However, the cost of purchase and maintenance of these instruments exceeds the budgets of most individual laboratories. The objective of the Cellular imaging Core, which is the result of the combination of two former IDDRC Cores, is to provide affordable access to state-of-the-art equipment. services, training and advice for projects using histological and imaging techniques. This new core, comprised of three components. Histology, Microscopy and Image Analysis, will build on the strengths and experience of the former cores, by providing a much more integrated set of services and capabilities. The Core continuously explores new technologies and has invested heavily in new equipment and image analysis software during the past grant period. As a result of these investments, the Core has greatly expanded its' repertoire of tools to visualize and analyze cellular processes, enabling IDDRC investigators to take their research to new levels. We are committed to maintaining this core as a central resource for neuroscience research at CHB and Harvard Medical School.